The group on Wednesday (9 December) reported "triple-digit growth" for passengers, bookings and revenue from the trade in the week to Tuesday 8 December.
In particular, JG said it had seen health interest in "themed" breaks, including trips to a new I’m A Celebrity attraction opening in Manchester next year.
Concerts and events such as Celine Dion and FriendsFestive are also proving popular, the group said.
JG revealed there had been an "immediate spike" in trade bookings for both JG’s JustGo! Holidays and National Holidays brands following England’s lockdown, which ended on 2 December.
"Once travel agency doors opened again, we were pleased to see an impressive surge in bookings from our agent partners," said Claire Dutton, JG trade sales manager.
"There’s been huge demand for events and attractions, as people obviously want to book something fun for next year.
"We’ve also seen a lot of 2021 festive bookings for products such as The Polar Express. These sold-out events were sadly cancelled this year due to restrictions, so customers want to book early for next year to avoid missing out."
The spike noted by JG aligns with a broader rebound in reports of interest in, and bookings for, domestic holidays highlighted in the latest TTG Travel Agent Tracker survey.
In the week to Friday 4 December, the number of respondents to the weekly survey reporting interest from clients in domestic breaks in the UK and Ireland increased from 9.5% to 27%, while the number reporting new bookings increased from 6% to 16.5%.
JG is making trips available on £10 low deposits, which are available up to Christmas Eve.
